721129311890 has 64 divisors (see below), whose sum is σ = 1496394345600. Its totient is φ = 247973819904.

The previous prime is 721129311839. The next prime is 721129311893. The reversal of 721129311890 is 98113921127.

It is not an unprimeable number, because it can be changed into a prime (721129311893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2328467 + ... + 2619926.

It is an arithmetic number, because the mean of its divisors is an integer number (23381161650).

Almost surely, 2^721129311890 is an apocalyptic number.

721129311890 is an abundant number, since it is smaller than the sum of its proper divisors (775265033710).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

721129311890 is a wasteful number, since it uses less digits than its factorization.

721129311890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4948491.

The product of its (nonzero) digits is 54432, while the sum is 44.

The spelling of 721129311890 in words is "seven hundred twenty-one billion, one hundred twenty-nine million, three hundred eleven thousand, eight hundred ninety".